Problem: Michael is 3 times as old as Emily and is also 16 years older than Emily. How old is Michael?
Solution: We can use the given information to write down two equations that describe the ages of Michael and Emily. Let Michael's current age be $m$ and Emily's current age be $e$ $m = 3e$ $m = e + 16$ Now we have two independent equations, and we can solve for our two unknowns. One way to solve for $m$ is to solve the second equation for $e$ and substitute that value into the first equation. Solving our second equation for $e$ , we get: $e = m - 16$ . Substituting this into our first equation, we get the equation: $m = 3$ $(m - 16)$ which combines the information about $m$ from both of our original equations. Simplifying the right side of this equation, we get: $m = 3m - 48$ Solving for $m$ , we get: $2 m = 48$ $m = 24$.